1. Field of the Invention
The present invention relates to a terminal apparatus with a transmission function for sending image data to another terminal apparatus, more particularly, it relates to an improvement of a terminal apparatus provided in, for example, a personal computer, which can send a natural image, such as a photo, to another terminal apparatus.
2. Description of the Related Art
Recently, communication between personal computers is widely utilized in digital communication networks, for example, an ISDN (Integrated Services Digital Network). Some types of personal computers can send natural images to another personal computer. This transmission function is very useful in the utilization of the ISDN since it is possible to directly send a photo, such as a sales catalog, to a user. Further, this transmission function which makes it possible to send natural pictures is useful, for example, in a teleconference system since it is possible to display a photo as a data display.
In general, such a terminal apparatus comprises a transmission means for sending the image data to another terminal, at least two storage means for storing the image data to be transmitted, a display means for displaying the image data to be transmitted and for confirming the content of the image data, and a control means for controlling the storage and transmission of the image data.
As a basic operation, input image data scanned from the natural image is stored in the storage means as RGB (red, green, blue) data, and the RGB data is displayed on the display means to confirm whether or not it is correct as the image data to be transmitted. Further, the RGB data is converted to luminance/color difference data. The luminance/color difference data is compressed and stored in the storage means, and the transmission means then sends the compression data to another terminal apparatus.
However, there is problem with the storage means in view of effective utilization of memory capacity as explained hereinafter.